Number 8 on "My Top 10 Most Useful Free Programs" is CCleaner. (available www.ccleaner.com).
CCleaner is another very useful program for removing unnecessary files. This one isnt intended as a Spy or Spam ware removal tool but is still very handy at letting you know what is usually ok to delete. It checks locations like TEMP files, Recycle bins, Temp Internet Files, cookies and log file that have accumulated.
The interface is very simple as well. ( See image below)
There are two main options. Analyse will do a scan and let you know how much will be saved after you Run. Run will actually clean up the files it found.
Some advance features include a Registry Scanner that attempts to find and repair problems.
It is amazing how much hard drive space is wasted over time. This tool will help you get some of it back.
I just re-ran it on my pc and it found another 5GB of space. Try it out and see how much it can find for you...